Stepping exercise machine



FIG. 1 is a perspective view of a stepping exercise machine showing my new design thereof;

FIG. 2 is a right side elevational view thereof;

FIG. 3 is a left side elevational view thereof;

FIG. 4 is a rear elevational view thereof;

FIG. 5 is a front elevational view thereof;

FIG. 6 is a top plan view thereof; and

FIG. 7 is a front perspective view of a modified embodiment of the design shown on FIGS. 1 through 6. 

The ornamental design for a stepping exercise machine, as shown and described. 